/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Arial', sans-serif;
}

body {
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

/* 导航栏样式 */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: #fff;
    padding: 15px 50px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.logo img {
    height: 40px;
}

.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin: 0 15px;
}

.nav-links a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #007bff;
}

.nav-links a.active {
    color: #007bff;
    font-weight: bold;
}

.user-actions {
    display: flex;
}

.login-btn, .register-btn {
    padding: 8px 20px;
    border-radius: 4px;
    text-decoration: none;
    margin-left: 10px;
}

.login-btn {
    background-color: transparent;
    border: 1px solid #007bff;
    color: #007bff;
}

.register-btn {
    background-color: #007bff;
    color: white;
    border: none;
}

/* 主要内容区域样式 */
main {
    width: 100%;
    max-width: 100%;
    margin: 0 auto;
    padding: 20px;
}

/* 轮播图样式 */
.slider {
    position: relative;
    height: 400px;
    overflow: hidden;
    margin-bottom: 40px;
}

.slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: #3498db;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: white;
    padding: 0 50px;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
}

.slide.active {
    opacity: 1;
}

.slide h2 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.slide p {
    font-size: 1.2rem;
    margin-bottom: 25px;
}

.cta-btn {
    padding: 12px 30px;
    background-color: white;
    color: #3498db;
    border-radius: 4px;
    text-decoration: none;
    font-weight: bold;
    transition: background-color 0.3s;
}

.cta-btn:hover {
    background-color: #f0f0f0;
}

/* 课程分类样式 */
.categories {
    margin-bottom: 40px;
    width: 100%;
}

.categories h2 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2rem;
    color: #333;
}

.category-cards {
    display: flex;
    justify-content: space-evenly;
    flex-wrap: wrap;
    width: 100%;
}

.category-card {
    flex: 0 0 22%;
    background-color: white;
    border-radius: 8px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    margin-bottom: 20px;
    transition: transform 0.3s;
}

.category-card:hover {
    transform: translateY(-5px);
}

.category-card img {
    width: 80px;
    height: 80px;
    margin-bottom: 15px;
}

.category-card h3 {
    color: #007bff;
}

/* 推荐课程样式 */
.featured-courses {
    margin-bottom: 60px;
    width: 100%;
}

.featured-courses h2 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2rem;
    color: #333;
}

.course-cards {
    display: flex;
    justify-content: space-evenly;
    flex-wrap: wrap;
    width: 100%;
}

.course-card {
    flex: 0 0 30%;
    background-color: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    margin-bottom: 20px;
    transition: transform 0.3s;
}

.course-card:hover {
    transform: translateY(-5px);
}

.course-card img {
    width: 100%;
    height: 160px;
    object-fit: cover;
}

.course-card h3 {
    padding: 15px;
    margin-bottom: 10px;
}

.course-card p {
    padding: 0 15px;
    margin-bottom: 15px;
    color: #666;
}

.course-btn {
    display: block;
    text-align: center;
    padding: 8px 0;
    background-color: #007bff;
    color: white;
    text-decoration: none;
    margin: 0 15px 15px;
    border-radius: 4px;
}

/* 页脚样式 */
.footer footer {
    background-color: #333;
    color: white;
    padding: 40px 0 0px;
    width: 100%;
}

.footer-content {
    width: 100%;
    max-width: 100%;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    padding: 0 20px;
}

.footer-section {
    flex: 1;
    margin-right: 30px;
}

.footer-section:last-child {
    margin-right: 0;
}

.footer-section h3 {
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.footer-section p, .footer-section a {
    color: #ddd;
    margin-bottom: 10px;
    display: block;
    text-decoration: none;
}

.footer-section a:hover {
    color: white;
}

.copyright {
    text-align: center;
    padding-top: 20px;
    margin-top: 20px;
    border-top: 1px solid #444;
    color: #aaa;
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        padding: 15px;
    }

    .nav-links {
        margin: 15px 0;
    }

    .user-actions {
        width: 100%;
        justify-content: center;
    }

    .slide h2 {
        font-size: 1.8rem;
    }

    .slide p {
        font-size: 1rem;
    }

    .category-cards, .course-cards {
        flex-direction: column;
    }

    .category-card, .course-card {
        width: 100%;
        margin-bottom: 15px;
    }

    .footer-content {
        flex-direction: column;
    }

    .footer-section {
        margin-bottom: 30px;
    }
} 